A further variant of the dynamic process principles is known from Narrow Gap Welding-The State-of-the-Art in Japan, The Japan Welding Soc., Tokyo, 1986, pages 65 to 73, in which the wire electrode is plastically deformed to form a helix by a rotating wire directing means, thus resulting in the end of the wire electrode carrying out a rotary movement during the welding process.
EP-A-0 557 757 discloses a method for narrow-gap welding of the type mentioned initially, in which the parameters welding current, electrode wire feed and inert gas tube separation are set without any mechanically activated electrode movement, in such a way that the normal axial material junction is dissolved by a rotating material with a rotating arc.
Both in the case of narrow-gap welding with a deflected wire electrode and in the case of narrow-gap welding with the arc itself being rotated, the weld joint width which can be bridged is limited as a result of which there is a risk of flank bonding faults when the gap widths are relatively large for production reasons.